Chiral method validation and stereoselective degradation of profoxydim isomers in paddy soil.

The herbicide profoxydim, which is chiral in nature, is commonly used for weed control in rice. However, traditional achiral analysis treats profoxydim isomers as a single compound, providing only partial and inaccuracy information assuming identical behavior for the four isomers. To address this issue, a sensitive and straightforward chiral analytical method was developed using QuEChERS and chiral HPLC-MS/MS to determine the residues of all four stereoisomers of profoxydim in soil.

Kinetic study, byproducts characterization and photodegradation pathway of profoxydim in a biochar water soil system.

The study focused on the photodegradation of profoxydim, a low-toxicity cyclohexanedione herbicide commonly used in rice crops, under simulated sunlight conditions. Profoxydim's behavior in paddy field conditions is not well understood, and this research aimed to fill that gap, particularly examining the effect of commonly utilized organic amendments such as biochar (BC) on its degradation. Results indicated that profoxydim degrades rapidly, with a half-life of 2.

Profoxydim in Focus: A Structural Examination of Herbicide Behavior in Gas and Aqueous Phases.

This study investigates the chemical structure of profoxydim, focusing on its E-isomer, the main commercial form. The research aimed to determine the predominant tautomeric forms under various environmental conditions. Using proton and carbon-13 NMR spectroscopy alongside theoretical modeling, we examined tautomers and their conformers in different solvents (MeOD, DMSO, CDCl, benzene) to mimic gas and aqueous phases.

Theoretical Study of Structural and Electronic Trends of the Sulfonylurea Herbicides Family.

The sulfonylurea herbicide family has been extensively studied using computational techniques. The most stable conformer structures of the 34 molecules analyzed in gaseous, aqueous, and octanol phases have been determined. The study employed CREST conformational search methods along with the CENSO script to explore all possible conformational structures.

Study of the different evaluation areas in the pesticide risk assessment process: Focus on pesticides based on microorganisms.

Both chemical and microbial active substances can currently be approved as pesticides in the EU, the provisions of their approval being set under Regulation (EC) No 1107/2009. Although sharing the same legal framework, chemicals and microorganisms used as pesticides have different risk profiles especially because once released into the environment, microbial active substances may produce secondary metabolites, multiply, spread and possibly genetically adapt or transfer antimicrobial resistance genes to other microorganisms. Consequently, the risk assessment process must adjust to the specificities ensuing from the chemical or microbial nature of the active substance.

A study using QSAR/QSPR models focused on the possible occurrence and risk of alloxydim residues from chlorinated drinking water, according to the EU Regulation.

Any active substance with phytosanitary capacity intended to be marketed in Europe must pass exhaustive controls to assess its risk before being marketed and used in European agriculture. Since the implementation of Regulation (EC) No 1107/2009, agrochemical companies have been obliged to study the formation of pesticide transformation products (TPs) during the treatment of drinking water containing pesticide residues. However, there is no consensus on how to address this requirement.

Analysis of Pesticide Residues by QuEChERS Method and LC-MS/MS for a New Extrapolation of Maximum Residue Levels in Persimmon Minor Crop.

According to EU guidance SANCO/7525/VI/95 Rev. 10.3, residue data extrapolation from a surrogate major crop to a minor crop can be used for setting maximum residue levels (MRLs) with a reduced number of residue trials and representative selected pesticides.

Study of the different evaluation areas in the pesticide risk assessment process.

Approval of active substances and authorisation of plant protection products in the EU is made based on a strict risk assessment of the agronomic use of the plant protection products. Regulation 1107/2009 regulates the procedure in the EU with complex procedures involving many actors. 'The Farm to Fork strategy' and 'The Biodiversity for 2030 strategy', that are the heart of the 'European Green Deal', aiming to make food systems fair, healthy, environmentally friendly and put Europe's biodiversity on the path to recovery by 2030, for the benefit of people, climate and the planet.

Computational-Based Study of QuEChERS Extraction of Cyclohexanedione Herbicide Residues in Soil by Chemometric Modeling.

Assessment of two buffered QuEChERS (quick, easy, cheap, effective, rugged, and safe) versions (i.e., citrate and acetate) modified by including methanol to recover the residues of three cyclohexanedione oxime (CHD) herbicides and three of their byproducts from agricultural soil was performed.

Considerations of nano-QSAR/QSPR models for nanopesticide risk assessment within the European legislative framework.

The European market for pesticides is currently legislated through the well-developed Regulation (EC) No. 1107/2009. This regulation promotes the competitiveness of European agriculture, recognizing the necessity of safe pesticides for human and animal health and the environment to protect crops against pests, diseases and weeds.

Photolysis of clethodim herbicide and a formulation in aquatic environments: Fate and ecotoxicity assessment of photoproducts by QSAR models.

The photochemical fate of the herbicide clethodim in natural waters was investigated under simulated and natural sunlight radiation. This herbicide exhibited a rapid degradation rate in simulated aquatic environment with half-lives ranged from 27.9min to 4.

The impact of restrictions on neonicotinoid and fipronil insecticides on pest management in maize, oilseed rape and sunflower in eight European Union regions.

Background: In 2013, the European Commission restricted the use of three neonicotinoids (clothianidin, imidacloprid and thiamethoxam) and the pyrazole fipronil, which are widely used to control early-season pests. Here, we used original farm survey data to examine the impact of the restrictions on pest management practices in eight regional case studies including maize, oilseed rape and sunflower in seven European Union (EU) countries.

Results: In four case studies, farmers switched to using untreated seeds as no alternative seed treatments were available.

Development of a rapid and direct method for the determination of organic acids in peach fruit using LC-ESI-MS.

An accurate, simple and rapid liquid chromatography mass spectrometry method for the determination of organic acids in peach fruit has been developed. Direct injection and sample clean-up with a mixed-mode sorbent was compared. The best results for the determination of gluconic, oxalic, malic, citric and fumaric acids were obtained with only a simple dilution and filtration step, and nylon filters should be avoided since some organic acids are retained by them.

Aqueous photodegradation of sethoxydim herbicide: Qtof elucidation of its by-products, mechanism and degradation pathway.

The photochemical fate of sethoxydim herbicide in water was studied under simulated sunlight radiation (Suntest apparatus). This compound exhibited a rapid degradation rate in water with a half-life of approximately 1h, which is in accordance with the high calculated value of the quantum yield (Φ=0.26).

Field-incurred fenitrothion residues in kakis: comparison of individual fruits, composite samples, and peeled and cooked fruits.

Field trials have been carried out to determine the variability of residue levels of fenitrothion and its main metabolites fenitrothion-oxon and 3-methyl-4-nitrophenol in individual kaki fruits versus composite samples, in peel versus flesh, and in whole uncooked versus whole cooked fruits. Residue levels have been determined by gas chromatography with thermionic specific detection after extraction with ethyl acetate and without further cleanup. At harvest, residue levels of fenitrothion were below maximum residue levels (MRLs) and the two metabolites 3-methyl-4-nitrophenol and fenitrothion-oxon could be quantified with average amounts of 0.

Occurrence, Distribution, and Relative Incidence of Mosaic Viruses Infecting Field-Grown Melon in Spain.

The main areas for field-grown melon (Cucumis melo) production in Spain were surveyed for the occurrence and relative incidence of cucumber mosaic virus (CMV), papaya ringspot virus-watermelon strain (PRSV-W), watermelon mosaic virus-2 (WMV-2), and zucchini yellow mosaic virus (ZYMV) during the growing seasons of 1995 and 1996. Samples from 1,152 plants showing symptoms of virus infection were collected from commercial melon fields and analyzed by enzyme-linked immunosorbent assay (ELISA). CMV and WMV-2 were the most frequently found viruses, both by the number of locations and by their incidence in each location.